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AR 601-280, Army Retention Program, Chapter 4, Chapter 4-2, Restrictions:
f. A Soldier in a transitional leave status awaiting ETS who changes his or her mind and desires reenlistment, may take the actions listed below.
(1) Soldiers last assigned to a CONUS installation are ineligible, but may return to that installation and apply for reenlistment as an exception to policy.
(2) Soldiers who departed an overseas command for the purpose of ETS are ineligible, but may return to the transition point where their records are located and apply for reenlistment under paragraph g below.g. Soldiers in an overseas area who are fully qualified for reenlistment, but elect to depart the overseas command for separation processing, will not be allowed to reenlist once they depart the overseas area. These Soldiers will be processed for immediate separation from the service upon arrival at the CONUS transition point. However, in exceptional cases, HRC, Retention Management Division, may authorize reenlistment for Soldiers who meet all the conditions below. Soldiers will apply from the closest CONUS installation transition point.
(1) The Soldier must be otherwise qualified for reenlistment without waiver.
(2) The Soldier’s PMOS must be shown as a shortage (Yes in/No out (Y/N) skill in the current HRC In/Out call message, or be an initial term SGT or a mid-career SSG (see Glossary).
(3) The Soldier must be recommended for reenlistment by the losing commander (the commander of the last overseas unit of assignment. This recommendation will be obtained by personnel at HRC, Retention Management Division.
(4) If approved, reenlistment option and/or assignment for these Soldiers will be determined by HRC. Soldiers who did not complete a normal overseas tour per AR 614-30 may be returned to the overseas command from which they departed.